The Patrol Division is the largest and most visible portion of the Department providing 24-hour protection, 365 days a year while the Criminal Investigation Division (CID) has the primary responsibility of investigating criminal matters that occur in the City.

The Waukesha Police Reserve Unit is a group of highly motivated and interested citizens from the Waukesha area organized to assist the Waukesha Police Department in routine matters, emergencies, and during special events as needed.